Light Cube What Is The Angle Of A Cone Of Light From A LED Inside A Cube Of Refractive Index N Surronded By Air?

What is the angle of a cone of light from a LED inside a cube of refractive index n surronded by air? - light cube

I searched the online help and my guide, but .... everything seems meaningless and knowledge would be useful.

When light is omni-directional in material refractive index in the form of a 3D rectangle and surrounded by n = 1, which is the angle of the beam is on each page? What happens to the rays of the others.